Method for fitting and installing microwaveguides

ABSTRACT

A method for modeling microwaveguides which comprises providing a plastic strip or Acrylic or Plexiglas, heating the strip until it is flexible, bending the heated strip to the desired shape of the waveguide and cooling in place until the plastic hardens.

United States Patent Inventor Ernest T. Long China Lake, Calii.

Oct. 17, 1968 Apr. 13, 1971 The United States of America, as

represented by the Secretary 01 the Navy Appl. No. Filed Patented Assignee METHOD FOR FITTING AND INSTALLING MICROWAVEGUIDES 1 Claim, 1 Drawing Fig.

U.S. Cl 29/600, 264/295, 264/339 Int. Cl ..1-l0lp 11/00 [50] Field of Search 29/407, (Cursory); 264/339 (X), 295 (X); 333/95 (Task);

[56] References Cited 4 UNITED STATES PATENTS 974,507 I 1/1910 McNabb 264/339X 2,381,367 8/1945 Quayle 333/95X 2,662,248 12/l953 Ames 264/339X Primary ExaminerAndrew R. Juhasz Attorneys-Edgar J. Brower, Roy Miller and Gerald F. Baker ABSTRACT: A method for modeling microwaveguides which comprises providing a plastic strip or Acrylic or Plexiglas, heating the strip until it is flexible, bending the heated strip to the desired shape of the waveguide and cooling in place until the plastic hardens.

Patented April 13, 1971 "3,574,928

ERNEST T. LONG ROY MILLER ATTORNEY.

' INVENTOR.

METHOD FOR FITTING AND INSTALLING MICROWAVEGUIDES BACKGROUND OF THE INVENTION The invention is concerned with the forming of microwaveguides for use in transmitter receiver complexes. In such a complex there may be existing structure and when it is necessary to install new equipment the new microwaveguide sections just be fitted through and around the existing waveguides. Previously, microwaveguides were fitted and installed using specifications and drawings or the waveguides were formed to match wooden models. However, it was difficult to obtain designs of minimum size and accurate fit and the construction process as a whole was expensive and time consuming.

SUMMARY OF THE INVENTION Briefly, the present method for fitting and installing microwaveguides involve the use of a strip of moldable plastic as a model for a waveguide in a microwave system. The plastic strip is heated until it is flexible and then the strip is bent to the shape desired to fit the system and held in place until the plastic rehardens. In view of the fact that the plastic strip can be cut to the same width and thickness of an actual waveguide, the model may be then simply duplicated thereby assuring an accurate fit and at the same time simplifying construction.

BRIEF DESCRIPTION OF THE DRAWING The FIGURE illustrates the invention.

DESCRIPTION OF THE PREFERRED EMBODIMENT In the FIGURE, the waveguide complex incorporates existent sections 10, II, 12 and 13. Also shown are various transmit-receive (TR) tubes 14, I5, switches I6, 17, junctions l8, l9 and high-power loads 20 and 21.

The waveguides which are used as the models are formed of the plastic material which may be heated and then molded. Such plastics may be Acrylic or conventional Plexiglas. In use, the plastic is cut to the desired final dimension of the waveguide, heated and then molded into an optimum path to conform to the final configuration.

Such portions are shown at 22, 23, and 24. The plastic models are illustrated as having flanges, for instance, on portions 23 at 25, 26 and 27. However, in actual practice the plastic would be formed in one continuous piece from the starting point to the stopping point and the flange position or any other parts to be inserted in the waveguide would be merely measured in the final waveguide and inserted in the guide section.

Thus, for instance, on a completed waveguide section such as one would have a flange 26 which would interconnect with a particular piece of equipment and interconnecting flanges 27 and 28. In the same fashion, waveguide section II- I2 when formed from the molded plastic would be one section. The TR tube 15 would be dimensioned and inserted in the waveguide finally fabricated. When the waveguide section is formed from, for instance, a magnesium alloy, the waveguide is matched to the particular dimension of the TR tube and inserted in the section. For instance, in the waveguide section 13 which tenninates in the TR tube 14 there is aphase shifter 29 between the TR tube 14 and the waveguide section 13.

In summing up, a moldable plastic is provided, heated until plastic, molded into place in a desired optimum configuration in the microwave complex, allowed to remain in situ until it hardens sufficiently to be handled, and then an actual waveguide section is configured on the model incorporating flanges, TR tubes, phase shifters, twist, etc.

Through the use of the present invention plastic strips can be bent to follow very complex curves and a complex microwaveguide system can be fitted and installed to take a minimum of space. In addition, the method can be used either for the design of new microwave systems or for remodeling and adding on to old systems. Further, plastic models can be color coded to correspond to color coding on the waveguides. Also, the plastic strips can be rebent until the correct fit is obtained and the method is considerably less time consuming and more accurate than methods incorporating the use of drawings or wooden models. Furthermore, the plastic used in the process may be reheated and reused as desired as long as it is feasible to do so. Last but not least, the method is both inexpensive and very fast.

The invention described herein may be manufactured and used by or for the Government of the United States of America for governmental purposes without the payment of any royalties thereon or therefor.

lclaim:

I. A method for fitting and installing microwaveguides comprising:

forming a full scale model of the waveguides using a material which may be rendered plastic and which has dimension corresponding to the desired cross section of a waveguide;

treating said material to render it plastic so that it may be shaped;

fitting and shaping the material in place to conform to the necessary spacial configuration desired for an actually installed waveguide;

maintaining the shaped material in situ until it returns to the original nonplastic state; removing said shaped material from the place where it was fitted and formed; and

using the formed and fitted material as a model, fabricating a finished hollow metal waveguide therefrom. 

1. A method for fitting and installing microwaveguides comprising: forming a full scale model of the waveguides using a material which may be rendered plastic and which has dimension corresponding to the desired cross section of a waveguide; treating said material to render it plastic so that it may be shaped; fitting and shaping the material in place to conform to the necessary spacial configuration desired for an actually installed waveguide; maintaining the shaped material in situ until it returns to the original nonplastic state; removing said shaped material from the place where it was fitted and formed; and using the formed and fitted material as a model, fabricating a finished hollow metal waveguide therefrom. 